Best way to remove CA?

Signed-In Members Don't See This Ad

barrysj

Member
Joined
Oct 2, 2009
Messages
125
Location
woodbridge va
So, after finishing the upper barrel perfectly, at times my lower barrel will just about be complete when the dreaded lifting of the CA happens ruining the blank.

Usually I skew off the 9 coats of medium CA then sand. This is painfully slow and introduces sanding marks etc.

So....has anyone found a better way to recover the blank to its original state so it is ready for CA again (other than this method). Some type of solvent that doesn't stain for example?

Thanks

Steve
 
Signed-In Members Don't See This Ad

Wood Butcher

Local Chapter Leader
Joined
Jun 8, 2005
Messages
970
Location
Westfield, IN, USA.
What do you mean by the CA lifting? It sounds like the wood could be wet, or at least wetter than it should be. Sounds like you have a fix that I woud employ but you may want to figure out why it's lifting. I apply 2 coats of thin to seal and penetrate the wood then start the medium. The 2 thin coats seem to give superior adhesion to the medium CA too.
WB
 

leehljp

Member Liaison
Joined
Feb 6, 2005
Messages
9,314
Location
Tunica, Mississippi,
That situation is precisely what caused me to change to TBC 5 years ago. NO more lifting. For me though it was consistent - on oily blanks such as cocobolo, rosewood or ebony. I turned the CA back down to the wood before changing methods. I did use CA on occasion but mostly just turned it. CA will bleed some woods and takes the sharpness of the color out.

I haven't had that (lifting) happen a single time since going to TBC.
 
Last edited:

Jgrden

Member
Joined
Mar 27, 2009
Messages
6,287
Location
hOUSTON, Texas
That situation is precisely what caused me to change to TBC 5 years ago. NO more lifting. For me though it was consistent - on oily blanks such as cocobolo, rosewood or ebony. I turned the CA back down to the wood before changing methods. I did use CA on occasion but mostly just turned it. CA will bleed some woods and takes the sharpness of the color out.

I haven't had that (lifting) happen a single time since going to TBC.

What's TBC?
 

Curly

Member
Joined
Nov 20, 2010
Messages
4,828
Location
Saskatoon SK., Canada.
TBC = Turning Between Centres. Centers for those below the 49th. ;)

Sent from my iPhone using Forum Runner because I can't reach my desktop!
 

Carl Fisher

Member
Joined
Jun 7, 2011
Messages
2,761
Location
Cape Coral, FL
Agreed. I do all of my finishing between centers with no bushings.

I fought the edges lifting as you describe for a while, but since switching to between centers, I haven't seen it since.

Sure it may take slightly longer to finish a 2 piece pen, but balance that against the time it takes to turn down a single ruined finish and start over and you'll come out ahead every single time.
 

jcm71

Member
Joined
May 5, 2011
Messages
1,660
Location
Chattanooga, TN
What do you mean by the CA lifting? It sounds like the wood could be wet, or at least wetter than it should be. Sounds like you have a fix that I woud employ but you may want to figure out why it's lifting. I apply 2 coats of thin to seal and penetrate the wood then start the medium. The 2 thin coats seem to give superior adhesion to the medium CA too.
WB

Concur. Although sometimes I get carried away and apply 4 to 6 coats of thin before switching to medium. I'm curious though. Why is TBC w/o bushings better to prevent this? Also, Why just one blank and not both ( going back to the original post)?
 

leehljp

Member Liaison
Joined
Feb 6, 2005
Messages
9,314
Location
Tunica, Mississippi,
What do you mean by the CA lifting? It sounds like the wood could be wet, or at least wetter than it should be. Sounds like you have a fix that I woud employ but you may want to figure out why it's lifting. I apply 2 coats of thin to seal and penetrate the wood then start the medium. The 2 thin coats seem to give superior adhesion to the medium CA too.
WB

Concur. Although sometimes I get carried away and apply 4 to 6 coats of thin before switching to medium. I'm curious though. Why is TBC w/o bushings better to prevent this? Also, Why just one blank and not both ( going back to the original post)?

Why is it better? Well you have to realize what causes the lifting:
1. Start with the fact that there is CA on the bushings with the same thickness as on the blank at the point where the bushings meet the blank.
2. Weak CA bond on some types of wood (oily woods), not necessarily green either.
3. Not everyone has surgeon type of hand control - Even cutting a parting ring near the joint of the blank and bushing does not always prevent the "snap" that causes "lifting".
4. The Snap of seperating the bushing from the blank with a weak bond of the blank causes the CA to "lift" and looks a little somewhat a part of a fingernail lifting.

Now, with TBC, there are no bushings for it to stick to. The dead center and live center fit into the tubes with no shoulders, so there is a direct drop off from the blank down to the two centers (hence Turning Between Centers). OF course some CA will get onto these but the breaking point is between the centers and the tubes, not the blanks. The "break" if there is one, is more between the centers and the tubes, than the blank.

In case something is missing for some here - measurements to sizing is done by calipers, not bushings and is FAR more accurate in fitting blanks to nibs, center bands and clip ends.


Why one blank and not both? Between centers live and dead center, you only turn one blank at a time.

To some, it is more time consuming but to me TBC is quicker. I can have a blank on and off the lathe in 2 to 3 seconds without having to rush. I pull a blank off the lathe sometimes 3 to 4 times to inspect it and measure it. ON a mandrel it takes 20 to 30 seconds EACH time you want to take it on and off for inspection. Some people don't do that, but I make lots of segmented pens, and as such I like to inspect them often. When I used mandrels, I would on occasion drop a spacer or a nut (several times over a year) and it would drive me crazy looking for them. With TBC, NEVER a problem because you don't use them. TBC is simple, Mandrels are complicated with many parts and flexing on the mandrel itself. The more parts, the more chances for mistakes, and if you keep score of TBC turners vs mandrel turners in numbers of problems, it is probably 10 to 1 in the number of problems of various kinds for mandrels in posts over the years, including the OP here.
 
Last edited:

barrysj

Member
Joined
Oct 2, 2009
Messages
125
Location
woodbridge va
To answer one question, it could be either the upper or lower barrel.

I also tbc, and Ifinish with tbc bushings and a small ring of brass the same size as the brass in the tube. This gives me the seperation I need like the tbc finishing method, without mucking up mr dead or drive centers. So it seals the edges pretty well, but on occasion I get the dreaded lifting on the edges. Mostly on koa and sometimes worthless wood blanks. I might try the thin ca approach to see if it helps. Thanks for the suggestions.
 
Top Bottom